Along with the rapid development of the display technology, touch panel has been widely used in our daily lives. Currently, depending on its structure, the touch panel may include an add on mode touch panel, an on cell touch panel and an in cell touch panel. For the add on mode touch panel, the touch panel and a liquid crystal display (LCD) panel are produced separately, and then attached together so as to form the LCD panel having a touch function. However, there exist for the add on mode touch panel such drawbacks as high manufacture cost, low light transmittance and thick module. For the in cell touch panel, a touch electrode of the touch panel is built in the LCD panel so as to reduce a thickness of the entire module and remarkably reduce its manufacture cost, so it has attracted more and more attentions from manufacturers.
Recently, liquid crystal display technologies capable of achieving a wide viewing angle mainly include an in-plane switch (IPS) technology and an advanced super dimension switch (ADS) technology. For the ADS technology, a multi dimensional electric field is formed by means of electrical fields generated at edges of slit electrodes within an identical plane and an electrical field generated between a slit electrode layer and a plate electrode layer, so as to enable all the liquid crystal molecules between the slit electrodes and right above the electrodes within a liquid crystal cell to rotate, thereby to improve the operational efficiency of liquid crystal molecules and enhance the light transmission efficiency. The ADS technology may be used to improve the image quality of a TFT-LCD product, and has such advantages as high resolution, high transmittance, low power consumption, wide viewing angle, high aperture ratio, low chromatic aberration and free of push Mura. H-ADS (high aperture ratio-ADS) technology is an important part of the ADS technology.
For the in cell touch panel based on the ADS technology and the H-ADS technology, a common electrode layer on the array substrate is divided into touch driving electrodes and common electrodes insulated from each other and arranged in a crisscross manner, and touch sensing electrodes are arranged on an opposite substrate at positions corresponding to regions where the common electrodes are located. The touch driving electrodes are driven in a time-division manner, so as to achieve a touch function and a display function. In the in cell touch panel, a projection of the touch sensing electrode onto the array substrate is located at the region where the common electrode is located, and the common electrodes and the touch driving electrodes are located at an identical layer and insulated from each other. In this way, it is able to prevent the touch sensing electrode and the touch driving electrode from overlapping each other in the projection direction and reduce a mutual capacitance formed by the overlapping area, thereby to increase the proportion of the mutual capacitance variation when a touch is made by a finger and improve the touch accuracy.
In the in cell touch panel, as shown in FIG. 1, which is a schematic view showing the divided common electrode layer, each common electrode 01 is a bar-like electrode, and each touch driving electrode 02 consists of a plurality of touch driving sub-electrodes 021, 022, 023, 024 arranged in an identical column. Each of the touch driving sub-electrodes 021, 022, 023 and 024 is arranged between the adjacent common electrodes 01. The touch driving sub-electrodes 021, 022, 023 and 024 belonging to the same touch driving electrode 02 and arranged at both sides of the common electrodes 01 are electrically connected to each other via a touch driving signal line 03. When it is required to achieve the display function, a common electrode signal is applied to the common electrodes 01 and the touch driving electrodes 02 simultaneously. However, because each touch driving electrode 02 consists of a plurality of separate touch driving sub-electrodes 021, 022, 023 and 024 while the common electrode 01 is a bar-like electrode, a signal transmission load of the touch driving electrode 02 is different from that of the common electrode 01, and the common electrode signal is transmitted in the common electrode 01 at a speed different from in the touch driving electrode 02. As a result, an uneven display image will occur and the image quality will be adversely affected.